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Topic: Camera availability (Read 1733 times)

I'm on the market for a camera for robotic vision, and so far the search has been pretty frustrating. My first choice was the Blackfin, but after a couple weeks of trying to get any kind of status report on my order from Surveyor on any of their contact emails or number I've pretty much given up on that and am in the process of trying to get my money back from PayPal (it's pretty funny that I couldn't even try to get a status on the order through their forum, as posting in it requires an account which needs to be created by the same people that aren't answering my emails to begin with...)

The only decent alternatives I've found are the CMUcam and the AVRcam, but neither of those are for sale anywhere I've found...this stuff isn't even listed on eBay, and all the retailer links I've found on Google are dead.

Any ideas on what I can do? I realize I could try to purchase all of the individual parts for a CMUcam and assemble it myself, but I'd really much rather buy a camera that's ready to be used. At this point I don't care which of the three cameras it is (although my preference is for Blackfin, then CMUcam 3, then CMUcam 2/AVRcam). Any ideas on where to look for one?

Edit: Note that this doesn't contain the blob detection firmware that things like the Blackfin do. So be prepared to write your own image processing - and if your robot has lots of other stuff to do then it may be very cpu intensive. If there is interest then I may get around to adding WebbotLib support. Available from the UK, rather than Australia, at http://www.robot-electronics.co.uk/acatalog/Cameras.html

Thanks, that actually looks very interesting. I had looked at similar 'simple' cameras before but they all had some kind of dealbreaker problem like only outputting JPEG, not providing a low enough resolution, or not providing TTL or I2C output, etc. This one seems like it has it all, initially I was worried about trying to do simple image processing in a microcontroller (due to the shortage of memory), but now that I think of it blob recognition and middle mass can be done on the image stream without actually needing to access the whole thing (I think it'll go with just a sliding window of horizontal resolution + 1 pixels).

I'll give some serious thought to one of these over the weekend, and I might get one just for the fun of actually coding a driver for it.

The other option I found is a NXTcam (http://www.mindsensors.com/index.php?module=pagemaster&PAGE_user_op=view_page&PAGE_id=78). This is more advanced (it has built-in blob and line recognition) and is accessible through a pretty nice I2C API, but the downside is that the image processing is pretty simplistic (no histograms, only 8 bins) and being closed source I can't improve it myself. Moreover, for that price I could just as well buy one of these uCAMs + a dedicated microcontroller just to handle image processing, and then hook that to my main MC via I2C or serial.

So...very tempted. If I buy a uCAM and write drivers for it (I'd say it's 75% likely, unless I have a big change of heart regarding NXTCam or somebody offers me a Blackfin for sale...), I'll post them here in case you want to add them to WBL.

Ugh, I think I just found the catch: the description on the site (a couple tabs in) says 0.75fps for preview images. I'm verifying this with tech support, but if that's all the camera can do it's just not going to be enough. I'm hoping that at a low-ish resolution and with 8-bit color it can do closer to 20fps. Otherwise I'll have to go with the NXT thingy.

I've no idea if they're legit but I'm crossing my fingers. I'll probably give them a call next week and if I can get an actual human being on the phone (I've no intention of repeating the Surveyor experience) I'll get a CMUcam 3.

Quick update on my search: so far, it's going poorly. The NXTCam pretty much can only do blobs and lines, which is really not gonna cut it--too much money for a platform with no extensibility and such reduced functionality. The uCAM apparently only does something around 1fps, which makes sense because you have to move the raw image (rather than the analyzed data) through the UART. I guess that's something I could live with if it was the absolutely only option available, but 1fps truly sucks if I want to use vision for motion planning, which I do.

I emailed the Hong Kong company and they answered...the bad news is no CMUCam3 in stock, and no lead time on them. I'm finding out if they have any 2, 2+, or 1 (which they only sell in kit form, but it's better than nothing I guess.)

I also found another camera out there: the POB-EYE (or POB-EYE 2). This one seems interesting, the built-in functionality seems to suck *but* it's also apparently fully programmable and has both UART and I2C connectivity. Looks like a poor man's CMUCam3 for the same price (but actually for sale somewhere, which at this point is starting to be a big plus.)

Has anybody used one of these POB-EYEs and has any comments on their quality?

Depending on your budget, I'd actually suggest a low-cost OMAP board (beaglebone, perhaps) and a USB webcam, as it gives you a fairly capable processor along with an extensible platform for about the same cost.

That's not a bad idea. Size and current draw are a bit of a concern, as is the fact that I'd need to build a shield for it to interface with everything else, but on the other hand the processing power looks phenomenal and the amount of on-board memory is ridiculous for a MC-sized board (256 *megabytes*?) Building the shield doesn't look terribly hard either, as the beaglebone appears to expose several UARTs and an I2C bus, so it should be little more than breaking everything out into a convenient layout and adding a power bus. Alternatively, maybe I'll just wire the I2C directly to an Axon and leave it at that.

In fact, this board looks so awesome that I might get one anyway even if I decide to go for a CMUCam. There's just no way I wouldn't find a good use for it...

I'm moving forward with the beaglebone+webcam approach, but I'll also try to get a smaller, low power consumption camera. For that the plan is to see if I can get an assembled CMUCam2, or else to build an AVRCam from scratch (better than a CMUCam1 and still doable without SMD soldering, unlike CMU2/3). That's kind of a long term project, though, as some of the parts (in particular the camera module) need to be ordered directly from China, and I'll have to recreate the schematic in KiCAD so I can get a PCB printed (the only schematic I've found is a crap quality image in the manual). The circuit needs some minor alterations as well, as I want a 6-pin programmer and a couple of the ICs need to be replaced with currently available models.

I never heard back from anybody at Surveyor, but I was able to get my money back from PayPal (who also couldn't get them to reply during the claims process). I give up on that...might try to pick a used Blackfin later or will give them another try if they get their act together.

In the meantime, I've ordered a CMUcam4. I agree the feature set is a lot more limited, but at least it's programmable (in Spin, ugh) and relatively cheap...and the only other stuff available for anything resembling a similar price is much worse.